the answer is -$97 for sure. 4 r* v; c1 \9 u0 Y4 ?8 ^' g
Think about it this way
6 N. B/ e$ l5 G8 z/ o' N* v1 U. ?tvb now,tvbnow,bttvb1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)5.39.217.77:8898. [( c% U3 i9 |5 O# w
2) Now, the owner discovered that the 100 bucks is fake. You can think this as a lost of $100. therefore the overall gain is $3-$100 = -$97 |